title: Diet and feeding selectivity of a benthivorous fish in streams: responses to the effects of urbanization.
abstract: This study evaluated the diet and feeding selectivity of the catfish Imparfinis mirini in streams with different degrees of urbanization and the effect of rainfall on the availability of prey. The diet was based especially on Chironomidae and Trichoptera. Significant spatial differences in diet were found between the streams; the diet of the fish was similar in the rural and peri-urban streams, and differed from that in the urban stream. Seasonality was an unimportant factor affecting the species' diet, which did not differ significantly between the rainy and dry periods in any of the streams. Fish from the urban stream fed more according to what was available in the environment, while fish from the peri-urban and rural streams showed higher degrees of selectivity. The results indicate that environmental conditions influenced the diet and prey selection of this species in response to the differences in diversity and abundance of the food organisms. They indicate that trophic studies of benthivorous fishes, such as I. mirini, may represent an alternative way to assess human effects on streams.
authors.affiliation: Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais-PEA, Universidade Estadual de Maringá-UEM, Avenida Colombo 5790, Jardim Universitário, CEP 87020-900, Maringá, Brasil. raffaeltofoli@gmail.com
authors.forename: R M
authors.initials: RM
authors.lastname: Tófoli
authors.forename: G H Z
authors.initials: GH
authors.lastname: Alves
authors.forename: J
authors.initials: J
authors.lastname: Higuti
authors.forename: A M
authors.initials: AM
authors.lastname: Cunico
authors.forename: N S
authors.initials: NS
authors.lastname: Hahn
mesh_terms: D000818:Animals; D002397:Catfishes; D004032:Diet; D005247:Feeding Behavior; D045483:Rivers; D014507:Urbanization
keywords: Imparfinis mirini; human effects; macroinvertebrates; predator-prey